Security Barcode

ABSTRACT

A security barcode is made up of modules that include optical disrupters that are too small to be deliberately placed in precise positions. The barcode is authenticated by a simple webcam including three-dimensional positioning means co-operating with a recognizable graphic structure referred to as a “marker”. In order to establish the authenticity of an article protected by the code, a description of the code is made after the code has been printed and is stored in a database, and that description is compared with a new description that results from at least two acquisitions, one made under the same conditions, and the other made while changing the three-dimensionally defined viewpoint and/or the lighting. In its preferred variant, the barcode cannot be printed in order to represent a predetermined number. It is also impossible to reproduce the barcode.

TECHNICAL FIELD

The present invention is an authentication method that makes it possibleto verify the authenticity of goods such as for example a printeddocument, by comparing the characteristics of an authentication device—abarcode—with the recording that has previously been made thereof. Theinvention also makes secure authentication possible for cards that arethemselves impossible to reproduce, for which it is necessary to havethe original available in order to perform transactions of all kinds(e.g. payment).

PROBLEM POSED

All kinds of goods and documents can suffer counterfeiting, with thisgoing from payment instruments to industrial goods, and includingofficial documents and pharmaceuticals. According to the World HealthOrganization (WHO), counterfeit pharmaceuticals represent 6% to 10% ofthe turnover of the worldwide pharmaceutical industry and lead to majorpublic health risks throughout the world.

According to the WHO Nov. 2, 2006 press release announcing the launch ofthe first international medical products anti-counterfeiting task force(IMPACT), “Counterfeit medicines are dangerous products. They promotedrug-resistant strains of disease and can worsen medical conditions orcause death. They are present on all markets and are increasing ascounterfeiters' methods become more sophisticated, infiltrating officialchannels of distribution as well as using illegal web sites to selltheir wares”. That phenomenon has continued to develop very greatlysince that press release.

This problem is particularly troublesome in that it has remained withouta solution for many years and it is getting worse. The solutionsproposed are all too expensive to be applied to consumer goods—includingpharmaceuticals in general circulation—and to all printed documents.

The difficulty lies in enabling a verifier, who may merely be anindividual, to compare an authentication device that is difficult orimpossible to reproduce with a recording that has been made of thedevice in question before it was put into circulation. This needs to bedone without using special equipment and must be very easy to do.

There exists a second unsolved problem that is of importance: in theprior art, the methods of authenticating personal cards rely on codesand it is impossible for anyone to know whether those codes have beenappropriated in one way or another by a third party, and no means havebeen proposed that make it essential to have the original of the card tohand, the card including a code for identifying a person on the Internetor for making a payment.

PRIOR ART

The making of security devices has relied for a long time on a principlethat consists in using complex technologies that are difficult forcounterfeiters to reproduce. The profitability of the activities ofcounterfeiters, and in particular of currency counterfeiters isnevertheless such that they always manage to counterfeit such devices.Three examples may be mentioned:

-   -   WO 2010/042999 A1 (Securency Internat Pty Ltd 2010 Apr. 22),        which describes a security device that is difficult to reproduce        and that includes a lens array serving to obtain “moire        magnification” of “moving or floating images” or other        “interesting optical effects”;    -   EP 2 166 486 A2 (Lumos Technology Co Ltd 2010 Mar. 24), which        describes a portable image extractor device (70) for identifying        tiny images with the help of a magnifying lens; and    -   US 2007/246932 (Heine Astrid et al. 2007 Oct. 25), which        describes a data medium with an optically variable structure        such that certain portions of the device are visible only under        one or more predetermined viewing angles.

The most appropriate state of the art for achieving the object sought bythe invention is represented by an older document: patent GB 2304077A(Farrall 1997 Mar. 12), which gave rise to patent US 2004/112962 A1(2004 Jun. 17) and which describes a device having reflective particlesthat are randomly distributed. Its author explains that it is possibleto compare a description of those particles with a description that isincluded in a database, however the scanner means proposed are verycomplex and specific.

The principle that consists in comparing the characteristics of anauthentication device with the recording that has been made of thatdevice in a database was thus devised by Farrall as from Jun. 30, 1995,the date on which patent application GB 2304077A was filed. Theprinciple of a device including particles that are randomly distributed,and even reflective particles, is also old since it is described in thatdocument.

Nevertheless, since that date, and in spite of the gravity of theproblem that is to be solved, and in spite of intense inventiveactivity, and large amounts of investment by numerous and powerfulcompanies that are specialized in the technical field—as can be seenfrom the large number of patent applications that have been filed inthis technical field—the problem still remains unresolved andcounterfeiting is progressing.

None of the more recent documents representative of the state of the artpresents a solution that genuinely answers the problem.

-   -   WO 98/45826 (Slater and Hardman 1998 Oct. 15), describes an        identification label constituted by a solidified plastics matrix        having a plurality of beads therein that can be distinguished by        eye and that are arranged randomly.    -   WO 01/57831 (Bourrières and Kaiser 2001 Aug. 9), describes a        method of reading means for identifying a unique and        non-reproducible volume comprising a mixture of at least two        mutually distinguishable materials, and remarkable in that it        consists firstly in recognizing the heterogeneous internal        structure in two dimensions of said identification means and        secondly in revealing and testing its third dimension, thereby        making any decoy impossible. But according to the inventors        themselves: “The identification and authentication of the        identifier is done with the aid of a specific reader which        allows the submission of the identifier to two different        illuminations and of comparing the signature of the identifier        presented with the one registered in the database. The necessity        to use a specific reader is also a major obstacle in the        extension of this technology in particular for applications to        the general public”.    -   WO 2004/054444 A1 (Bourrières and Kaiser 2004 Jul. 1), describes        an indirect method of identification and authentication without        using an article reader, with the help of a three-dimensional        identifier attached to said article, the identifier presenting        non-uniformities that are randomly distributed inside a        transparent material thus making the material difficult or        impossible to reproduce. That method has the announced advantage        of not requiring a reader, but it relies entirely on human        vision and is therefore not reliable.    -   US 2009/008924 A1 (Ophey Willem Gérard et al.—2009 Jan. 8)        describes a method of authenticating a device having        physically-detectable particles embedded in a substrate. That        method includes a digital representation of the physical        properties of the particles and of their distribution, but it        does not propose any means for ensuring that the security device        has not been replaced by a photograph of an existing device.    -   US 2010/200649 A1 (Callegari Andrea et al.—2010 Aug. 12),        describes a marking method relying on a random distribution of        particles having the property of reflecting circularly polarized        light, in association with corresponding authentication        equipment. That makes it easy to distinguish the marking from        its medium even when the medium is colored and/or reflective.        Its drawback is that it requires the use of two light sources        that are polarized in different ways, together with particles        that reflect circularly polarized light in a special way.

The explanation for the failure of the prior art is simple:

1) All prior art methods suffer from one and/or more of the followingthree drawbacks:

-   -   the authentication devices used can be fabricated only by making        use of means that are rare and expensive, and as a result they        are too expensive to be applied to consumer goods and to        everyday documents;    -   or else they are large in size, and therefore difficult to        incorporate in goods or a document;    -   or indeed no method is proposed for reading them other than        using a microscope or some other specially designed and        expensive accessory device.

2) No one has proposed a flawless and inexpensive method that satisfiesthe need of professionals and of the general public to verify theauthenticity of goods or of a document using ordinary equipment such asa mobile telephone.

3) Nor has anybody proposed a procedure for authenticating people thatmakes it essential to have available the original of a card, regardlessof whether people are face to face or communicating over the Internet,and in spite of the fact that identity theft is one of the main sourcesof fraud, in particular on the Internet.

SUMMARY OF THE INVENTION

The present invention provides an authentication method consisting inestablishing a “subsequent” description of an authentication device 1that comprises a “coded” entity 11, itself comprising light-disruptingelements referred to as “disrupters” 111, 112, et seq., and in comparingthis description with an “original” description of said authenticationdevice 1, the method being characterized by the facts:

-   -   that said disrupters 111, 112, et seq. are grouped together in        sub-entities 1A, 1B, et seq. referred to as “modules”, a module        returning light in perceptibly different ways depending on the        point of view from which it is observed;    -   that a description includes an operation referred to below as        “acquisition” that consists in using acquisition means 3 for        measuring the brightness of a plurality of said modules 1A, 1B,        et seq., at one or more wavelengths or sets of wavelengths;    -   that said original description is established from an        acquisition made from an “original” viewpoint defined relative        to said authentication device 1; and    -   that the procedure enabling said subsequent description to be        established and enabling said comparison to be made comprises:        -   using positioning means that co-operate with a recognizable            graphics structure referred to as a “marker” 2 to determine            the three-dimensional position in which said acquisition            means 3 are located relative to said authentication device            1;        -   taking an acquisition while said acquisition means 3 are            placed close to the original viewpoint; and        -   taking at least one “additional” acquisition:            -   either from a viewpoint that is perceptibly different                from said original viewpoint;            -   or else under lighting that is different from that used                for the acquisition that was used for establishing said                original description.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention can be well understood and other objects, advantages, andcharacteristics thereof appear more clearly on reading the followingdescription, which is illustrated by FIGS. 1 to 14.

FIG. 1 shows a portion of an authentication device 1 of theauthentication method of the invention, the device being constituted bya print medium 100 and a coded entity 11 forming a transparent layer inwhich disrupters 111, 112, et seq. are embedded.

FIG. 2 shows a business card protected by an authentication device 1 ofthe invention having four modules 1A, 1B, 1C, and 1D situated in theproximity of the four corners A, B, C, and D of the card, theconfigurations of these four modules constituting a recognizablegraphics structure referred to as a “marker” 2.

FIG. 3 shows an authentication device 1 of the authentication method ofthe invention, constituted by a transparent print medium 100, a codedentity 11 forming a transparent layer in which disrupters 111, 112, etseq. are embedded, and an optional magnifying optical device 12constituted by lenses 121, 122, et seq. In this embodiment the marker 2is constituted by the black surface between the lenses.

FIG. 4 shows an authentication device 1 of the authentication method ofthe invention constituted by a print medium 100, a coded entity 11comprising a reflective ink layer of varying thickness constituting saiddisrupters 111, 112, et seq., and an optical magnifier device 12constituted by a transparent film 120 and by lenses 121, 122, et seq.

FIG. 5 shows an authentication device 1 having 64 modules 1A, 1B, etseq. organized as a checkerboard of eight rows by eight columns. Themarker 2 is constituted by a reflective surface 200 provided with atarget 202 in its center.

FIG. 6 shows the reflective surface 200 of an authentication device 1with edges 200A, 200B, et seq. that are reflective and rounded.

FIG. 7 shows a device of the invention made up of a prior art barcode 50of the Datamatrix type associated with 32 modules 1A, 1B, 1C, et seq.,organized as a circular ring. The device has a marker 2 in the form of aseries of two concentric circles constituted by the two edges ofcircular ring.

FIG. 8 shows an optical device referred to as an “image multiplier” 6that provides a plurality of images of said authentication device 1. Itis constituted by four plane prisms 61, 62, 63, and 64.

FIG. 9 shows a lens 121 having its iris defined by a circle 1211. Thislens focuses on a surface 1212 referred to as a “focus surface”,including a zone 1213 referred to as a “significant zone”.

FIGS. 10 to 12 show how the position of said focus surface 1212 variesrelative to said significant zone 1213 as a result of said acquisitionmeans 3 moving relative to said authentication device 1.

FIG. 13 shows a device of the invention comprising a marker 2 andacquisition means 3 comprising an image multiplier 6 and positioningmeans 7 that need to be caused to coincide with said square marker 2 inorder to place said acquisition means 3 at said original viewpoint.

FIG. 14 shows a device 1 of the invention comprising a marker 2 made upof two edges projecting from the goods provided with said authenticationdevice 1, and acquisition means 3 comprising positioning means made upof two re-entrant angles 71 and 72 that need to be made to coincide withthe projecting edges 21 and 22 forming said marker 2 in order to causesaid acquisition means 3 to be placed at said original viewpointrelative to said device 1.

DETAILED DESCRIPTION OF THE INVENTION The Principle

The principle of the present invention consists in authenticating anauthentication device 1 by comparing a description of the device 1,which description is referred to as a “subsequent” description, with adescription of the same device 1, which description is referred to as an“original” description. Each of the characteristics of the methodoperates in synergistic manner with the others in order to obtainauthentication that is reliable.

-   -   Said disrupters being grouped together in sub-entities 1A, 1B,        et seq. referred to as “modules” that reflect light in        perceptibly different ways depending on the viewpoint from which        they are observed gives the device all of the advantages of        barcodes: its description may be limited to describing each of        the modules 1A, 1B, et seq. in binary form (a module is written        1 when it is pale and 0 when it is dark) or with only a few        digits representing its brightness and/or its color.    -   Determining the three-dimensional position in which said        acquisition means 3 are located relative to said marker 2 of the        authentication device 1 makes it possible to place said        acquisition means 3 at said original viewpoint, or failing that        at a location that is close enough thereto to be able to verify        that at least a large portion of the device provides an        appearance that is substantially identical to that described in        said original description of said authentication device 1. In        this respect, it is important to observe that the accuracy        required for this positioning depends on the nature of the        disrupters 111, 112, et seq., and on the nature of the modules        1A, 1B, et seq., and that various methods are described below to        make it possible for this positioning to be carried out with        lower accuracy.    -   Successively acquiring two images from two different locations        makes it possible to verify the nature of the authentication        device 1:        -   modifying the position of the acquisition means 3 and the            position of the lighting makes it possible to verify that            such modification does indeed lead to a modification in the            image that is received and thus in the description, thereby            proving that the device has not been replaced by an            imitation, e.g. a photographic imitation; and        -   modifying the lighting also makes it possible to neutralize            the effect of ambient lighting, and/or to verify the            light-reflection properties of the disrupters of or any            other portion of the device.

Advantageously, the disrupters are small enough to ensure that a deviceof the invention cannot be reproduced by a counterfeiter without thatrequiring each reproduction to be very costly (or indeed to becompletely impossible with known fabrication means).

An important advantage is that the authentication device 1 can befabricated using equipment and technologies already available toprinters, i.e. the same printers as are used for fabricating thedocuments or the packages that are to be protected. This makes the costof fabricating an authentication device 1 of the invention marginal andenables the invention to be generalized, in particular forpharmaceuticals and other consumer goods, and also to very manydocuments that might be forged.

The Coded Entity

Said disrupters may be protected by a layer of varnish or printed on therear face of a transparent print medium. As shown in FIG. 1, it is alsopossible to incorporate disrupters 111, 112, et seq. in a block oftransparent substance, e.g. a plastics card or a key ring.

A layer of varnish with an irregular reflective surface may be combinedwith disrupters placed randomly in a second layer of varnish placedunder the first layer, in order to constitute a coded entity 11 that isvery fine and very complex, and therefore very difficult to reproduce.

Said modules 1A, 1B, et seq., may be contiguous, where the notion of a“module” is determined at the time the description is established,however it is advantageous for the modules to be spaced apart from oneanother by surfaces referred to as “separation” surfaces that do notinclude any disrupters visible from said acquisition means 3. Theseseparation surfaces advantageously present a combined surface area of atleast 5% of the total surface area of the modules 1A, 1B, et seq. Thismakes it possible to have no doubts about which one of said modules anyparticular disrupter belongs.

It may be advantageous to print a grid defining boxes each defining oneof said modules 1A, 1B, et seq. in order to mark said disrupters 111,112, et seq. situated outside zones that are defined as constitutingsaid modules.

The color of said separation surface is an important point. When thedisrupters 111, 112, et seq. are bright, the color is advantageouslydark, but when they are not bright it is desirable for said separationsurfaces to pass light. A good solution is to make these surfacestranslucent in order to mask the disrupters situated between two moduleswhile providing good lighting of the disrupters being observed.

Said disrupters 111, 112, et seq., may be arranged in organized mannerby the designer of the device. Some or all of them may alsoadvantageously be distributed randomly. This procures two majoradvantages:

-   -   they can be very small, which prevents them from being        reproduced; and    -   they can be printed in large quantities with a print system that        always performs the same print function, e.g. by mixing the        disrupters in an ink that is translucent or transparent and        always printing the same pattern with an offset plate.

In order to create an “original” description, it is possible tophotograph the authentication device 1 on the fabrication line from adetermined viewpoint, e.g. using a camera situated at said originalviewpoint. This original viewpoint is determined relative only to theauthentication device 1 and can therefore be found subsequently.

A description may also be made without taking a photograph when thearrangement of the disrupters is organized by the designer of thedevice.

An authentication device 1 of the invention may also have boxes of twotypes, firstly boxes that have the same appearance regardless of theposition of the acquisition means 3 and regardless of the lighting, andsecondly modules 1A, 1B, et seq. of the invention that return light inperceptibly different ways depending on the viewpoint from which theyare observed.

FIG. 7 shows an example of such a mixed device. The center has a code 50of the type known as a Datamatrix code, and the code is surrounded by acircular ring made up of modules 1A, 1B, et seq. that return light inperceptibly different ways depending on the viewpoint from which theyare observed.

In a preferred embodiment, said disrupters 111, 112, et seq. presentperceptibly different appearances depending on the direction of thelight rays they receive, e.g. by reflecting or by polarizing or byfiltering the light differently depending on the direction in which thelight in question is received. This has the effect of causing theappearance of the authentication device 1 to depend on the position ofthe observer and also on the position of the light source.

Under such circumstances, it is necessary for the position of a lightsource to be the same for said original description and for saidsubsequent description so that the orientation of said disruptersobserved while creating said subsequent description is indeed the sameas that taken into account when creating said original description.

A light source used for establishing said subsequent description isadvantageously the light projector of said acquisition means 3, e.g. aflash or a light-emitting diode (LED) of the camera or the smartphone.Some of said disrupters reflect light towards the acquisition means 3,while others do not.

It should be observed that using disrupters that reflect and/or transmitlight in perceptibly different ways depending on the direction of thelight rays they receive makes it possible to increase the number ofdescriptions that are possible for a given viewpoint, by varying theposition of the light source(s) while retaining the same viewpoint.

In an embodiment of the invention shown in FIG. 4, said disrupters areportions of the surface of a layer of material that reflect and/ortransmit light differently from the print medium 100 or from thepreceding ink layer. By way of example, it may be a layer of ink orvarnish applied on a print medium 100 and having surface tension that isso much less than the surface tension of the ink or varnish underconsideration that said ink or varnish is repelled and forms irregularrandom spots on said print medium 100.

These irregular random spots may be of negligible thickness, howeverthey could also be of sufficient thickness for the bodies of the spotsand their edges to reflect light in different directions. It is alsopossible to use the variations in thickness of said layer to generatereflections in other directions.

Said disrupters may also be reflective chips such as for example flakesor metal or of plastics material coated in a reflective coating. Theymay also be elements that are transparent with a refractive index thatis different from the index of the material in which they are embedded.

The advantage of using disrupters that are bright is that, even whilespread over a plane surface so as to form a set of thickness that isvery small or negligible, they nevertheless provide appearances thatdiffer depending on the viewpoint from which they are observed, in amanner that would be done by a device that is three-dimensional andtherefore much more bulky.

A second advantage is that the image that is captured is stronglycontrasted and easy to analyze regardless of the environment, even whenthe disrupters are very small.

Said disrupters 111, 112, et seq., are advantageously invisible to thenaked eye, i.e. they have a maximum dimension of less than 85micrometers (μm) (which is equivalent to a resolution of 300 dots perinch (dpi), which is usually considered as being the limit of theresolving power of the human eye situated at the accommodation nearpoint).

They are advantageously as small as possible so that a counterfeiterfinds it difficult to reproduce a device of the invention, so small asto make it impossible with any known method to deliberately deposit adisrupter in a determined position (to copy disrupters that are arrangedrandomly).

In a preferred embodiment as shown in FIG. 1, said coded entity 11 is ofthickness that enables said disrupters to be placed at differentdistances from the print medium 100, thereby considerably increasing thenumber of images of the authentication device 1 that can be seen fromdifferent viewpoints. To make counterfeiting more difficult, it isadvantageous for said coded entity 11 to be of thickness that is greaterthan the thickness of the smallest disrupter used, because under suchcircumstances parallax differences appear between the views of theauthentication device 1 taken from different viewpoints. Advantageously,said coded entity 11 is of a thickness that is not less than twice thegreatest dimension of the smallest disrupter 111 used.

In another preferred embodiment, at least one of said disrupters 111,112, et seq. includes a reflective plane that is not parallel to themain plane of said device. This makes the device more difficult toreproduce, since a set of disrupters situated in the same plane can besimulated by a printed reflective plate.

Some of the flakes 111, 112, et seq. advantageously have their mainplanes inclined relative to the main plane of the authentication device1 so as to obtain a reflection from a viewpoint that is not situatedvertically relative to the device when its main plane is horizontal.This makes it easier to acquire a device of the invention by acquisitionmeans 3 having an objective lens close to the light source, since it isthen possible to move the device away from any reflection of the lightsource in question on the main plane.

The light beam reflected by the flake 111 generally has a solid anglethat is very small since the areas of the light source and of the flakeare both very small. This can result in very great variability in theimage of the device 1 as perceived by the acquisition means 3 for a verysmall movement thereof.

When said acquisition means 3 are held in the hand, it then becomesdifficult to position it close enough to the original viewpoint.

It is therefore advantageous to provide the authentication device 1 withan optical diffuser. This has the effect of causing the light beamreflected by the disrupter 111 to leave said authentication device 1with a solid angle that is greater than that of the beam entering saiddevice and subsequently received by said disrupter. This opticaldiffuser may be a frosted surface situated on the front face of theauthentication device 1, however it is also possible to embed thedisrupters in a varnish that is not completely transparent but that istranslucent, or in a varnish having particles that deflect light.

Another method of reducing the accuracy required in positioning saidacquisition means 3 consists in using disrupters 111, 112, et seq.having surfaces that diffuse the light reflected, e.g. a frostedsurface, or microstructures such as a reflection hologram. The personskilled in the art knows how to design holograms having at least onevery small point that reflects white light in the form of a light beamof differing wavelengths and having a solid angle that is greater thanthat of the received beam. This very small point, constituting thedisrupter, has a location that is very accurate relative to thedisrupter containing the hologram, and it is therefore difficult or evenimpossible for a counterfeiter to position it deliberately.

Said disrupters 111, 112, et seq. may also be beads that are transparentor translucent. They are advantageously embedded in a layer of inkhaving low transparency and of thickness that is equal to or greaterthan their diameter. Such a bead is visible only via its portion that istangential to the top surface of the ink or close thereto. This visibleportion, which constitutes the disrupter, is also very small comparedwith the size of the bead in question and its location is thereforelikewise difficult to determine deliberately. It may be possible forlight to pass through a transparent or colored bead in certaindirections only, depending on its position. The rear face of the codedentity 11 may be colored randomly and/or may be reflective.

In the above-described embodiment, the device of the invention iscapable of operating equally well with lighting situated beside itsfront face or in transparency with lighting situated beside its rearface. The person skilled in the art can imagine numerous otherstructures having this capability.

Said disrupters 111, 112, et seq. may be obtained by printing an inkhaving surface tension that is greater than that of the print medium.This has the effect of the ink clumping randomly as drops that are veryfine and tall.

A large difference in surface tension between the print medium and theink has the drawback of the ink adhering poorly to the medium. To avoidthat drawback, it is advantageous for said disrupters 111, 112, et seq.to be covered in a varnish that adheres to the print medium. Thisvarnish serves to fasten them permanently.

One possible improvement consists in a material used in making saidcoded entity 11—such as for example the material used for some of saiddisrupters—to become visible under a particular kind of radiation, suchas ultraviolet radiation, for example.

The person skilled in the art may also arrange materials havingdifferent refractive indices or that filter different colors or thatpolarize light in random manner between said disrupters and the outsideface of the authentication device 1, in order to limit the reflection oflight and/or in order to prevent a counterfeiter being able tounderstand the real optical configuration of said coded entity 11 or ofany other element of said authentication device.

In order to make the system more complex and more difficult tocounterfeit, said disrupters 111, 112, et seq. may be of shapes and/orcolors that differ from one to another.

In an application to games and in particular to lotteries, theauthentication device 1 may include means serving to ensure that all orpart of said coded entity 11 cannot be seen clearly, with it beingdifficult for such means to be put back into their original state afterthey have allowed it to be seen clearly. One known solution consists inapplying a layer of ink that is easy to remove by scratching. Under suchcircumstances, it is desirable for this scratchable ink layer to be keptseparate from the coded entity 11 by a strong film. This can be done byprinting the scratchable layer on the front face of the device andprinting the coded entity on its rear face.

In a particular embodiment, the authentication device 1 is a label whichis destroyed at least in part on being unstuck. Such a label is shown inFIG. 5. This embodiment serves to protect existing documents or goods,such as works of art, bottles of vintage wine, aviation or automotivespare parts, or official documents, for example.

In a preferred version, said disrupters 111, 112, et seq. are mixed withthe adhesive of said label so that the way they are organized isdisrupted during any attempt to unstick the label. Advantageously, theadhesive strength of the adhesive on the portion of the label thatincludes said marker 2 is less than its adhesive strength on the mediumon which the label is stuck. Thus, during an attempt at unsticking, saiddisrupters are separated from the portion of the label that includessaid marker 2.

(Optional) Optical Device 12

The authentication device 1 of the invention is advantageouslyassociated with an optical device 12 made up of a plurality ofindividual optical devices 121, 122, et seq.

Such an individual optical device 121 may be a converging lens. Thismakes it possible to magnify the disrupters 111, 112, et seq. optically.

By way of example, an individual optical device 121 is a convex lensthat may be spherical or cylindrical and that is focused on a plane thatis close to or included in said coded entity 11.

The magnifying optical device 12 may be a device of the kind known as alens array, however it is used differently in the invention: instead ofbeing used to produce a particular visual effect such as animation,representing a photograph three-dimensionally, or moire magnification,or indeed to make it difficult to understand how the coded entity 11 isorganized, it is used mainly to enable some of said disrupters 111, 112,et seq. to be seen from a distance. Lens array devices are known for usein the context of security devices, e.g. from U.S. Pat. No. 4,417,784(Knop & Gale 1983 Nov. 29) which explains that by combining a codedimage with a lens array, it is difficult for the coded image to beunderstood and thus to be reproduced. That principle has been taken upin numerous documents including U.S. Pat. No. 5,543,965 (A) (Bielinski &Herber 1996 Jul. 6), which describes an auto-stereoscopic lens displayhaving an image generated by creating a plurality of random points.Those prior art devices have the drawback of being easy to reproduce forthe person skilled in the art having appropriate equipment.

The first advantage of such a device is to make it possible to seedisrupters that are smaller and therefore that are organized in a mannerthat is correspondingly more difficult to reproduce. The secondadvantage is that the coded entity 11 may be of thickness that is verysmall or negligible, even though the authentication device 1 presentsappearances that are very different depending on the viewpoint fromwhich the disrupters are observed, as would occur in a three-dimensionaldevice that is much less compact.

The converging optical devices 121, 122, et seq. have a focal planesituated in the immediate proximity of said coded entity 11, and each ofthem has the effect of optically magnifying said disrupters situated inthe alignment of the objective lens of the optical acquisition means 3and of the optical center of the lens under consideration, whileignoring said neighboring disrupters. The decoder may thus be smaller insize while providing an image of the same resolution that is easy tophotograph with an ordinary camera.

An authentication device 1 may be constituted by a transparent printmedium 100, said magnifying optical device 12 being printed on one faceof said print medium 100 and said coded entity 11 on the other face ofsaid print medium 100.

It may also be constituted by a coded entity 11 printed on a printmedium 100 and by a magnifying optical device 12 fitted onto said codedentity 11. The magnifying optical device 12 may be constituted by atransparent film having lenses on one of its faces, said film beingadhesively bonded via its other face onto said coded entity 11. Saidtransparent film may also be constituted by a thickness of varnishcovered in lenses 121, 122, et seq. so that the distance between thefocus of a lens and a disrupter element is sufficient.

The distance between the focus of a converging optical device and adisturber is advantageously less than the focal length of the convergingoptical device in question, but it may also be substantially equal tosaid focal length or greater. The important point is for the opticaldevice to magnify the appearance of the disrupter element.

The converging optical devices 121, 122, et seq. may be contiguous orthey may be spaced apart from one another, they may be arrangedregularly or otherwise, they may be distributed randomly, and they mayall have the same focal length or they may have focal lengths thatdiffer from one another, thus making it even more difficult to copy anauthentication device 1 of the invention.

An individual converging optical device 121 may also be concave mirrorsituated behind the coded entity 11. This embodiment (not shown) has theadvantage of making it possible to make authentication devices that arefiner than those that make use of convex lenses.

An individual optical device 121 may also be a diverging device. Thismakes it possible to reduce the sensitivity of the device to variationsin the position of said acquisition means 3.

In a particularly recommended embodiment, a module 1A has only oneindividual optical device 121. This enables the module to have alocation that is well-determined and unchanging, and that is easy toidentify in three dimensions when analyzing the acquisition performed bysaid acquisition means 3, while also ensuring a strong differencebetween the appearances of the various modules from a given viewpoint.

Creating Said Original Description

The term “description” is used herein to mean any type of computer filemade from an acquisition performed either by computer simulation or byany optical acquisition means 3, such as a camera, a scanner, a barcodereader, etc. . . . . For example it may be a photograph of the deviceseen from said original viewpoint.

A device of the invention may have the appearance of a 2D barcode suchas those known under the names Datamatrix or Maxicode or indeed QR code,with the exception that it provides information that differs dependingon the position of the observer.

Numerous different methods may be used for describing a module 1A, suchas, for example: the maximum or minimum or mean brightness in one ormore colors of the pixels that make it up. The use of minimum or maximumvalues makes it possible to rule out surfaces that do not include anydisrupter that is visible from said acquisition means 3 and that aresituated outside the zone of a module that is deemed to be significant,and to give values that are very different to modules each having aplurality of disrupters.

Another way of writing a description consists in noting the brightnessof modules of the coded entity 11 having one or more characteristics incommon, e.g. by noting the coordinates of the modules that are brightestat an agreed wavelength.

An “original” description may be recorded in said database onfabrication of the authentication device 1, however it may also becreated after said authentication device 1 has been put into service.

This task may thus be given to the user of the device. The acquisitionmeans 3 for use subsequently in obtaining the subsequent descriptionwill then have exactly the same optical characteristics as the devicethat was used to make the original description, since it is the samedevice that is used for both operations. This constitutes an additionaladvantage.

In the most usual situation, an original description of theauthentication device 1 is conserved in a database.

It is also possible for a plurality of original descriptions of theauthentication device 1 corresponding to different viewpoints or todifferent lighting to be conserved in said database. This has the effectof increasing the number of possible combinations. In order to makefraud more difficult, this requires a plurality of comparisons to bemade with a plurality of original descriptions from viewpoints or withlighting characteristics that differ from one comparison to the next.

Said database may be conserved in the memory of a computer controllingsaid acquisition means 3, however it is also possible for said“original” description to be conserved in a server computer capable ofcommunicating with said acquisition means 3, and possibly alsoconserving a secret suitable for use in the authentication procedure.

Under such circumstances, it must be ensured that communication betweensaid acquisition means 3 and said remote computer server is secure.

Once said original description has been established, said authenticationdevice 1 may be marked with an “additional identification” elementestablished on the basis of the original description. This additionalidentification element may comprise all or part of said originaldescription.

It is possible for two authentication devices of the invention, and inparticular for devices including disrupters 111, 112, et seq. that aredistributed randomly, to be found to be completely identical afterfabrication in the sense that they generate the same originaldescription. They can then advantageously be distinguished by suchmarking.

With certain very accurate devices, a small movement of said acquisitionmeans 3 may lead to an undesired modification of the “subsequent”description. To avoid that, it is advantageous for said originaldescription of the authentication device 1 to be calculated while takingaccount of multiple acquisitions of said authentication device 1,corresponding to different viewpoints and to different lighting. Byperforming a plurality of acquisitions from viewpoints close to saidoriginal viewpoint, it is possible to distinguish between portions ofthe device 1 that are subject to such undesired variations, and otherportions that may be considered as presenting values that are modifiedlittle by a small movement of said acquisition means 3, where suchportions are referred to below as “reliable portions”.

An original description derived from these “reliable portions” may thustake the form of a number. The procedure for distinguishing betweenauthentication devices of the invention for which mere acquisition ofthe random cells would lead to the same original description—asexplained above—makes it possible for this number to be made unique. Itcan then be used as the unique identifier of the authentication device1, and thus of the goods or documents with which it is associated.

Advantageously, a description may comprise the definition of these“reliable” portions, and their scores. By ignoring the other portions ofthe device, a description is obtained that does not depend on precisepositioning of said acquisition means 3 during a “subsequent”acquisition.

The comparison between said subsequent description and said originaldescription then relates only to said disrupters for which saidbrightness scores obtained during said two acquisitions have values thatdiffer by an amount that is less than some freely predeterminedthreshold. The optimum threshold, i.e. the threshold that corresponds tothe accuracy of said means for positioning the acquisition means 3, maybe freely determined by the person skilled in the art.

Taking a plurality of acquisitions from viewpoints close to saidoriginal viewpoints can be made easier if said acquisition means 3 isprovided with a said image multiplier 6 that provides a plurality ofimages of said authentication device 1. Such an image multiplier opticaldevice 6 is shown in FIG. 8. It comprises four plane prisms 61, 62, 63,and 64. When placed between the acquisition means 3 and theauthentication device 1, as shown in FIG. 13, it provides four images ofsaid authentication device, corresponding to different viewpoints.

When said disrupters 111, 112, et seq. present perceptibly differentappearances depending on the direction of the light rays they receive,each of the prisms may be masked when taking an image, e.g. using aliquid crystal device, so that the light source used does not passthrough the prisms that do not correspond to the viewpoints beingacquired. Four acquisitions are then taken in succession.

The person skilled in the art knows how to juxtapose other numbers ofprisms so as to make acquisitions from some other number of differentviewpoints, e.g. nine or sixteen by juxtaposing nine or sixteen prisms.

The Authentication Procedure

The two acquisitions of said device 1 in the authentication proceduremay be performed in succession with said acquisition means 3 orsimultaneously with a plurality of acquisition means.

The comparison between the two acquisitions, one taken with ambientlighting only and the other with additional lighting, enables the personskilled in the art to deduce therefrom a difference suitable forcalculating a description from which the effect of ambient lighting iseliminated.

For an authentication device 1 of the invention that has an “additionalidentification” element, the authentication procedure need not requireaccess to a telecommunications network: said subsequent description iscompared at least in part with all or part of said additionalidentification element established from said original description. Inorder to prevent a counterfeiter fabricating devices of the invention,it is recommended to encrypt said identification element in asymmetricmanner: a private key for use in performing such coding is not madeavailable to the public, while a public key that allows the applicationto decrypt the element is made available to the public or only to peopleauthorized to perform authentication operations.

Positioning

Determining the three-dimensional position in which said acquisitionmeans 3 are located relative to said authentication device 1 is anessential step in the acquisition procedure using said acquisition means3.

The position may be determined by instructions given to the operator, orby using a template on which the acquisition means 3 must be placed, asshown in FIGS. 13 and 14. Under such circumstances, a plurality ofacquisition means and a plurality of light sources may be available inorder to avoid any need to use mechanical means during the acquisitionprocedure (versions not shown).

In a preferred version, the acquisition procedure nevertheless beginswith a step of three-dimensional positioning that is computer-assisted.

The telemeter forming part of said acquisition means 3 makes it possibleto determine the distance between the acquisition means 3 and theauthentication device 1, however it is simpler to measure the apparentsize of the device, which increases as said acquisition means 3 comeclose to said authentication device 1.

Said determination of the position in which said acquisition means 3 arelocated relative to said authentication device 1 may include measuringdeformation due to the perspective of the image as perceived by saidacquisition means 3 and affecting some or all of said authenticationdevice 1, and/or of the goods or the document carrying theauthentication device 1. It is thus possible to calculate thethree-dimensional position of the acquisition means 3 relative to saidauthentication device 1. A computer connected to said acquisition means3 can perform calculation to deduce the direction of the movement to beapplied to said acquisition means 3 in order to bring it closer to saidadditional viewpoint. When the acquisition means 3 comprise a camera,the movement to be applied thereto is specified by a visual indicationon the screen, and the camera can acquire images during the procedurewhile finally conserving only the desired acquisition(s).

In order to evaluate the position of said acquisition means 3 with thebest possible accuracy, it is recommended to analyze the deformation dueto the perspective of the image of the largest possible component of theprotected document or goods, e.g. its outline if it is constituted by alabel. During fabrication, it is also possible to place markers on theprotected document or goods for use in this analysis of the deformationof the image due to perspective.

As shown in FIG. 2, the identification device 1 may also be sharedbetween a plurality of modules 1A, 1B, et seq. situated at variousspaced-apart locations, and the image perceived of these locations maybe used as a marker for evaluating the position of said acquisitionmeans 3.

A marker 2 is advantageously constituted by one or more circles such asthose shown in FIG. 7, which are easy to detect, and known methods areavailable for easily analyzing their deformation due to perspective.Numerous 3D vision methods exist that enable primitives to be detectedby homographic transformation. The standardized direct linear transform(DLT) algorithm is one of the best known of these methods and it solvesa set of variables of a set of similarity relationships. It eliminatesthe need to make initial approximations, as are required for non-linearsolutions.

One of the known methods is described in EP 1 143 372 B1. It is aprocedure for reading a two-dimensional barcode symbol havingorientation modules and a search pattern with a central point, themethod including in particular executing a step of searching for datamodules in order to calculate position and shape information for all ofthe modules making up the barcode symbol, which can be omitted in thecontext of the present invention, while retaining only the scanning ofthe positioning outline and determining its central point within thescanned image.

Another method of determining the position in which said acquisitionmeans 3 are located relative to said authentication device 1 consists inproviding the authentication device with a marker 2 constituted by areflective surface 200 having a target 202.

The reflective surface 200 may be incorporated in the device, or it maybe separate, being removable and being placed thereon when making anacquisition. The first advantage of a removable reflective surface 200is to simplify the structure of the device, since the reflective surface200 is then a transparent plastics sheath or a glass plate. The secondadvantage is that it is possible to use a large reflective area 200 eventhough the protected goods are very small, e.g. a unit package for apharmaceutical.

Said determination of the position in which said acquisition means 3 arelocated relative to said authentication device 1 advantageously includesdetecting a reflection on said reflective surface 200 of acharacteristic element of said acquisition means 3 or of a light sourcesecured to said acquisition means 3.

Said original viewpoint is then advantageously defined relative to saidauthentication device 1 as being situated on the straight linerepresenting the reflection on said reflective surface 200 of a lightray coming from said characteristic element 201 and passing via saidtarget 202.

In order to place said acquisition means 3 at said original viewpoint,the user need only move the acquisition means until the characteristicelement 201 can be seen at an agreed location of said reflective surface200, e.g. a target 202.

When said characteristic element 201 is said light source, saidreflective surface 200 may present very poor reflective quality, e.g.such as that of ordinary coated paper, since that is sufficient toenable the user to identify the position of the reflection of said lightsource on said reflective surface 200. Advantageously, said reflectivesurface 200 is nevertheless a surface covered in a bright varnish.

Under numerous circumstances, said reflective surface 200 needs to bevery small in order to avoid taking up too much space on the goods ordocument for protection. An improvement of the present inventionconsists in providing it with reflective curved surfaces 200A, 200B, etseq., e.g. constituted by the edges of said surface as shown in FIG. 6.The reflection of the light source on said rounded edges gives theposition of the light source even when it is remote from the desiredposition, since the reflection is on a surface facing sideways when thelight source is far away in the direction corresponding to that side.

The position of the reflection of said light source can be analyzed by acomputer so that the user receives simple instructions concerning thedirection in which said acquisition means 3 should be moved so as to beplaced at said original viewpoint.

Whatever the method used for determining the position in which saidacquisition means 3 are located relative to said authentication device1, it is advantageous to assist the user in placing said acquisitionmeans 3 in the position corresponding to said original viewpoint. Thesearch for the most ergonomic solution leads to said acquisition means 3having a screen, with the screen displaying a stationary graphic and avirtual graphic indicating the position of said original viewpoint,thereby informing the user about the direction in which said acquisitionmeans 3 should be moved in order to be placed in the locationcorresponding to said original viewpoint. The virtual graphic iscalculated by computer, and may be displayed in such a manner as tocoincide with said stationary graphic when said acquisition means 3 arein the location corresponding to said original viewpoint.

Acquiring the Code

In order to limit acquisition errors, it is particularly advantageousfor the creation of a description to consist, for each module, inanalyzing an area that is greater than the area of the module underconsideration, said area extending from the module over a zone that doesnot include any disrupters visible from said acquisition means 3. It istherefore more probable that each module will indeed be taken intoaccount in full.

FIGS. 9 to 12 show an organization of the authentication device 1 of theinvention that makes it possible to limit variation in the image of thedevice as perceived by said acquisition means 3 for very small movementsof the acquisition means, when the authentication device 1 includes anoptical device 2 itself made up of a plurality of individual convergingoptical devices 121, 122, et seq. With this organization, an individualconverging optical device 121 focuses on a “focus” surface 1212 thatincludes a “significant” zone 1213 including disrupters, and saidsignificant zone is smaller than said focus surface and is surrounded bya zone that does not include any disrupters. Thus, when said acquisitionmeans 3 are moved a little, all of the disrupters taken into account insaid original description remain visible through the individualconverging device under consideration without any other disruptersbecoming visible.

The stage of causing said acquisition means 3 to approach said originalviewpoint is a good occasion for performing additional acquisitions. Adescription may thus be created and stored during a stage in which saidacquisition means 3 are approaching said original viewpoint.

Multiple descriptions may also be established by the user. Pairs[description a, position a], [description b, position b] et seq. arethen advantageously created and stored throughout the stage in whichsaid acquisition means 3 are approaching said original viewpoint.

Telecommunications Security

It is particularly advantageous for only a portion of said subsequentdescription to be transmitted to said computer server for comparisonpurposes. The definition of which part to transmit may be different foreach authentication operation, and may even be performed randomly.

In a preferred version, a secret is provided by said computer server.The authentication procedure then cannot be performed without connectingto the server. In a preferred version, the secret is provided in realtime by said computer server. Said secret may comprise an algorithmdefining the way in which all or part of said subsequent description isto be calculated and transmitted to said computer server. The definitionof which portion of said subsequent description is to be transmitted tosaid computer server may be defined by said algorithm, which may bedifferent from the algorithm used for a preceding transmission of saidsubsequent description. It may also include an encryption key.

It is particularly recommended not to provide pirates with thedefinition of the transmitted portion and to encrypt this informationusing a key that is provided in real time by said computer server.

A preferred solution consists in the secret comprising a code for singleuse. The secret may be encrypted by a key constituted in full or in partby a number calculated from said subsequent description, which may beknown to said computer server.

In order to increase the security of authentication operations, it isadvantageous for the secret to include a random number that istransmitted by said computer server at the end of an operation ofcomparing a “subsequent” description with an “original” description, andfor this random number to be requested by said server in order toauthorize the following comparison operation.

This method is recommended when a secret code of the invention is usedfor creating a card to authenticate a person, e.g. in order to enablethat person to access functions personal to that person on an Internetsite. A pirate might have read the description of the code of theinvention as present on the card and then might simulate sending aportion of the code with counterfeit software. The need to send a randomnumber received during the preceding operation makes it necessarysimultaneously to steal the computer or the mobile telephone of thebearer of the card. Other known methods make it possible for the serverto verify the integrity of the software hosted by said acquisition means3.

Advanced Procedures

In some circumstances, the acquisition procedure using said acquisitionmeans 3 is advantageously launched by a command that includes, directlyor indirectly, the address of a client seeking to obtain a result ofcomparing said subsequent description with said “original” descriptionof said authentication device 1. By way of example, the client may be abank seeking to certify the postal address of the holder of anelectricity bill including a code of the invention. This holder isreferred to below as the “billee”. The code may include the postaladdress of said billee, or a code making it possible to obtain it from aserver of the issuer of the electricity supplier. Either way, saidcommand requests the billee to give permission to the electricitysupplier to forward his or her personal address to said bank, and theoperation includes providing said bank with a link making it possible toobtain the address. This link is advantageously associated with asingle-use password that is valid for a limited duration.

The acquisition procedure with said acquisition means 3 isadvantageously launched by a command contained in a file opened by thecomputer application managing said acquisition procedure. The file maybe received by email, or it may be obtained by clicking on a link. Itsuffices for the nature of the file to be associated with theapplication for authenticating a code of the invention to enable theoperation to be made automatic and very simple to perform for the user.

Said command may be launched by reading a barcode. The barcode maycontain the address of a client seeking to obtain a result of thecomparison of said subsequent description with said “original”description of said authentication device 1, or the Internet address atwhich said address can be found.

Said barcode may be displayed on the screen of another computer. Thisenables a second computer to read it by acquiring the code with itscamera. This constitutes practical means for transferring informationfrom a computer to a mobile telephone, for example.

An improvement in the method consists, after the comparison of saidsubsequent description with said “original” description of saidauthentication device 1, for said computer server to send an Internetlink making it possible to recover information relating to the resultsof the comparison.

To return to the above-mentioned example of a bank and an electricitybill, the electricity supplier does not send the address of the holderbut rather sends a link making it possible to recover that address.

Communication of the link may be accompanied by providing acryptographic key making it possible to decrypt the transferred data.This prevents the data being captured by a pirate while it is beingtransferred.

This method of selectively extracting data provides considerable noveltyin the transfer of data from server to server, since it makes itpossible physically to limit data communication to no more than thelegitimate needs of the beneficiary, as defined by law and as selectedby the person to whom the data relates.

This method is also monitored and made secure since it requires anagreement of the person concerned by the data and it is secure: itrequires a personal document to be presented such as a card or a billincluding the code of the invention, which cannot be reproduced, and itrequires the data to be encrypted while it is being transferred overtelecommunications networks.

Said database may be updated either before codes of the invention areput into service, or later. If updated later, an important task istransferred to the client instead of being performed by the supplier ofthe service.

Nevertheless, care must be taken to ensure that it is not possible forsomeone to pass themselves off as someone else and give a fraudulentvalue to codes of the invention.

The method used is as follows:

-   -   an authentication device 1 is associated in said database with a        person referred to below as the “user”;    -   it is given to said user by known means making it possible to be        sure of the identity of said user, such as for example sending        by registered mail to the personal address of said user; and    -   said user subsequently updates said database with information        relating to the article fitted with said authentication device        1.

Methods of Fabricating the Authentication Device 1

It is possible to fabricate a device of the invention by very many knownprinting methods, using an ink having two immiscible materials, e.g.solid disrupters 111, 112, et seq. embedded in a transparent ink thatbecomes solid after polymerizing or drying. This method is compatiblewith practically all printing techniques using liquid or powder ink.

It is also possible to use an ink-jet printer to spray the transparentink and the disrupters, or to spray ink to different colors, some ofwhich act as disrupters.

It is also possible to print a pattern with the reputation of beingdifficult to print, e.g. having zones for printing or not printing thatare too small, thereby having the effect that the capillarity of the inkcauses it to clump together in the form of random zones.

Another method consists in printing a pattern on a medium that hassurface tension that is very low compared with that of the ink beingused. The ink being repelled by the medium causes the ink to move inapplication of rules that are very complex and difficult to predict andthus to reproduce.

The methods described above have the major advantage of being printingmethods that can be the same as the methods that are used forfabricating the goods to be protected by the authentication system ofthe invention.

Said optional magnifying optical device 12 may be obtained either bylaminating a film including one or more converging lenses, e.g. embossedtherein, or more advantageously by printing lenses by applying a varnishconstituting lenses directly on said coded entity 11 or on anintermediate layer of varnish, or on a film fitted thereon.

Three main fabrication techniques are proposed, leading to differentstructures for a device of the invention.

-   -   It is possible to print the disrupters 111, 112, et seq.        directly on the document or goods to be protected, and        optionally to cover the set with a layer of varnish that        optionally includes converging optical devices.    -   It is possible to print the disrupters 111, 112, et seq. on a        sheet of paper that is very fine and fragile, that is itself        stuck with strong adhesive onto a silicone-coated medium, and        optionally to cover the set in a layer of varnish optionally        including converging optical devices. The device can easily be        unstuck from the silicone-coated medium in order to be put into        service on goods or a document to be protected, however        thereafter any attempt at unsticking the device inevitably leads        to the sheet of paper being torn and thus to the destruction of        the coded entity 11.    -   It is possible to print the disrupters 111, 112, et seq. on the        rear face of a transparent sheet that optionally includes        converging optical devices on its front face. The transparent        sheet is then stuck via its rear face on a silicone-coated        medium using strong adhesive that may advantageously be the        transparent element containing said disrupters. The coded entity        11 is unchanged when the device is unstuck from the        silicone-coated medium, but thereafter any attempt at unsticking        it inevitably leads to the coded entity 11 being destroyed.

The converging optical devices 121, 122, et seq. of said optionalmagnifying optical device 12 may be made using any means, such as forexample printing a transparent ink, using known techniques such as thosedescribed in the following documents: WO 2009/147353 (Guigan et al.,2009 Dec. 10); PCT/FR2011/000315 (P. Guigan 2010 Jun. 30); U.S. Pat. No.6,833,960 (J. S. Scarbrough 2004 Dec. 21); U.S. Pat. No. 6,856,462 (J.S. Scarbrough 2005 Feb. 15); and U.S. Pat. No. 7,609,451 (J. S.Scarbrough 2009 Oct. 27). Under such circumstances, the convergingoptical devices 121, 122, et seq. are printed structures, and the entireauthentication device 1 can be made by a conventional printing method,which may be that used for printing the goods or the document that is tobe protected from counterfeiting or fraud, thereby considerably reducingthe cost of the authentication device 1 so that this cost becomessubstantially negligible.

Applications

Applications go well beyond those of the existing marketing for securitydevices:

-   -   health: pharmaceuticals, prescriptions, certificates, etc.;    -   protecting trademarks: labels, cases for goods, authentication        seals, boxes, cartons, flexible sachets, capsules, bags, blister        packs, bottles, pots, cabinets, etc.;    -   payment: bank notes, checks, credit cards, coupons, etc.;    -   ticket: travel tickets, entertainment tickets;    -   official documents: driver licenses, residence permits, log        books, insurance certificates, social security cards, identity        cards, passports, voter cards, postal stamps, diplomas, member        or loyalty cards, tickets for transport or entertainment,        prescriptions, certificates of origin, etc.;    -   economic activity: business paperwork, headed notepaper, deeds        and contracts, receipts, vouchers, bank statements, securities,        bills, pay slips, judgments, orders, certificates, etc.;    -   printing media: security paper for office printers or ready for        printing by professional printers, etc.;    -   any goods on which it is possible to print: jewelry, watches,        spare parts and supplies, consumer electronics, components and        consumables, data media (CDs, DVDs, etc.), labels for clothing        and other fashion articles, local crafts, etc.;    -   labels ready for sticking on any article (works of art, pieces        of furniture, wines, jewelry, etc.);    -   various: games and lotteries, traceability, logistics, etc.; and    -   goods belonging to some particular world (organic food,        fairtrade, food prepared in compliance with the rules of such        and such a religion, etc.).

Having recourse to a central server may be essential for authenticatingthe origin of goods or a document, and this can make it possible toestablish statistical information concerning the destinations of goodsand documents and even, by comparing a plurality of authenticationoperations performed by a given user, making it possible to have abetter understanding of the behavior of consumers.

One of the major fields of application of the invention lies in secureidentification of people, in particular on the Internet: on-linepayment, authentication of emails and contracts, secure transfer of dataand funds, secure access to intranets and to personal pages,communicating encryption keys, and more generally obtaining rights onall kinds of site, in particular bank sites, social sites, game sites,etc.

1. An authentication method consisting in establishing a subsequentdescription of an authentication device that comprises a coded entity,itself comprising light-disrupting elements referred to as “disrupters”,and in comparing this description with an original description of saidauthentication device, wherein: said disrupters are grouped together insub-entities referred to as “modules”, with a module returning light inperceptibly different ways depending on the point of view from which itis observed; a description includes an operation referred to below as“acquisition” that consists in using acquisition means for measuring thebrightness of a plurality of said modules, at one or more wavelengths orsets of wavelengths; said original description is established from anacquisition made from an original viewpoint defined relative to saidauthentication device; and the procedure enabling said subsequentdescription to be established and enabling said comparison to be madecomprises: using positioning means that co-operate with a recognizablegraphics structure referred to as a “marker” to determine thethree-dimensional position in which said acquisition means are locatedrelative to said authentication device; taking an acquisition while saidacquisition means are placed close to the original viewpoint; and takingat least one additional acquisition: either from a viewpoint that isperceptibly different from said original viewpoint; or else underlighting that is different from that used for the acquisition that wasused for establishing said original description.
 2. An authenticationdevice suitable for performing the authentication method of claim 1,wherein the device comprises: a coded entity of disrupter elementsgrouped together in sub-entities referred to as modules, with a modulereturning light in perceptibly different ways depending on the viewpointfrom which it is observed; and a recognizable graphics structurereferred to as a “marker” enabling positioning means to determine theposition in which said authentication device is to be found relative toacquisition means
 3. 3. The authentication device according to claim 2,wherein said modules are separated from one another by separationsurfaces that do not include any disrupters visible from saidacquisition means, and wherein said separation surfaces presenting acombined area that is not less than 5% of the total area of the modules.4. (canceled)
 5. The authentication device according to claim 2, whereinall or some of said disrupters are distributed randomly.
 6. Theauthentication device according to claim 2, comprising two types of box,firstly boxes having the same appearance regardless of the position ofthe acquisition means and regardless of the lighting, and secondly boxesthat are modules of the invention.
 7. The authentication deviceaccording to claim 2, wherein said disrupters present appearances thatare perceptibly different depending on the direction of the light raysthey receive.
 8. The authentication device according to claim 7, whereinat least one of said disrupters includes a reflective plane that is notparallel with the main plane of said device.
 9. The authenticationdevice according to claim 2, further including an optical diffuser. 10.(canceled)
 11. (canceled)
 12. (canceled)
 13. (canceled)
 14. Theauthentication device according to claim 2, comprising means making itpossible to prevent some or all of said coded entity being seen clearly,which means are not capable of being returned to an original stateeasily after being taken out of service.
 15. The authentication deviceaccording to claim 2, wherein it is a label that is destroyed at leastin part on being unstuck.
 16. The authentication device according toclaim 15, wherein said disrupters are mixed with the adhesive of saidlabel.
 17. (canceled)
 18. (canceled)
 19. (canceled)
 20. (canceled) 21.(canceled)
 22. (canceled)
 23. (canceled)
 24. (canceled)
 25. (canceled)26. The authentication method according to claim 1, wherein an originaldescription of the authentication device is stored in a database and aplurality of original descriptions of the authentication devicecorresponding to different viewpoints or to different lighting arestored in said database.
 27. (canceled)
 28. (canceled)
 29. A method offabricating authentication devices according to claim 1, whereinestablishing said original description is followed by marking saidauthentication device with an additional identification element that isestablished from the original description and wherein when it is foundthat two devices have the same original description corresponding to thesame viewpoint, they are distinguished by such marking.
 30. Theauthentication method according to claim 1, wherein said originaldescription of the authentication device is calculated while takingaccount of at least two acquisitions of said authentication device thatcorrespond to two different viewpoints or to two different lightingconditions.
 31. (canceled)
 32. (canceled)
 33. (canceled)
 34. Theauthentication method according to claim 1, wherein said subsequentdescription is established by comparing two acquisitions of said devicetaken by said acquisition means, one using ambient lighting on its ownand the other using additional lighting.
 35. (canceled)
 36. (canceled)37. (canceled)
 38. (canceled)
 39. The authentication method according toclaim 1, wherein the screen of said acquisition means display astationary graphic and a virtual graphic giving the position of saidoriginal viewpoint.
 40. The authentication device according to claim 3,wherein creating a description consists, for each module, in analyzingan area greater than the area of the module under consideration, saidarea projecting beyond said module over a zone that does not includedisrupters.
 41. (canceled)
 42. The authentication method according toclaim 1, wherein a description is created and stored during a stage ofapproaching said acquisition means to said original viewpoint. 43.(canceled)
 44. The authentication method according to claim 1, whereinthere exists a computer server capable of communicating with saidacquisition means and having stored therein said original descriptionand/or a secret useful in the authentication procedure and wherein asecret is provided by said computer server.
 45. (canceled) 46.(canceled)
 47. (canceled)
 48. The authentication method according toclaim 44, wherein the secret comprises a random number transmitted bysaid computer server at the end of an operation of comparing asubsequent description with an original description, and wherein therandom number is requested by said server in order to authorize thefollowing comparison operation.
 49. (canceled)
 50. (canceled) 51.(canceled)
 52. (canceled)
 53. (canceled)
 54. (canceled)